ansible.builtin.command module – Execute commands on targets

ansible.builtin.command module – Execute commands on targets

https://docs.ansible.com/projects/ansible/latest/collections/ansible/builtin/command_module.html

This module is part of ansible-core and included in all Ansible installations. In most cases, you can use the short module name command even without specifying the collections keyword. However, we recommend you use the Fully Qualified Collection Name (FQCN) ansible.builtin.command for easy linking to the module documentation and to avoid conflicting with other collections that may have the same module name.

Synopsis

Parameters

Attributes

Notes

See Also

Examples

Return Values

Synopsis The ansible.builtin.command module takes the command name followed by a list of space-delimited arguments.

The given command will be executed on all selected nodes.

The command(s) will not be processed through the shell, so operations like “*”, “<”, “>”, “

”, “;” and “&” will not work. Also, environment variables are resolved via Python, not shell, see expand_argument_vars and are left unchanged if not matched. Use the ansible.builtin.shell module if you need these features.

To create command tasks that are easier to read than the ones using space-delimited arguments, pass parameters using the args task keyword or use cmd parameter.

Either a free form command or cmd parameter is required, see the examples.

For Windows targets, use the ansible.windows.win_command module instead.

Note

This module has a corresponding action plugin.

Parameters Parameter

Comments

argv list / elements=string

Passes the command as a list rather than a string.

Use argv to avoid quoting values that would otherwise be interpreted incorrectly (for example “user name”).

Only the string (free form) or the list (argv) form can be provided, not both. One or the other must be provided.

chdir path

Change into this directory before running the command.

cmd string

The command to run.

creates path

A filename or (since 2.0) glob pattern. If a matching file already exists, this step will not be run.

This is checked before removes is checked.

expand_argument_vars boolean

added in ansible-core 2.16

Expands the arguments that are variables, for example $HOME will be expanded before being passed to the command to run.

If a variable is not matched, it is left unchanged, unlike shell substitution which would remove it.

Set to false to disable expansion and treat the value as a literal argument.

Choices:

false

true ← (default)

free_form string

The command module takes a free form string as a command to run.

There is no actual parameter named free_form.

removes path

A filename or (since 2.0) glob pattern. If a matching file exists, this step will be run.

This is checked after creates is checked.

stdin string

Set the stdin of the command directly to the specified value.

stdin_add_newline boolean

added in Ansible 2.8

If set to true, append a newline to stdin data.

Choices:

false

true ← (default)

strip_empty_ends boolean

added in Ansible 2.8

Strip empty lines from the end of stdout/stderr in result.

Choices:

false

true ← (default)

Attributes Attribute

Support

Description

check_mode partial

while the command itself is arbitrary and cannot be subject to the check mode semantics it adds creates/removes options as a workaround

Can run in check_mode and return changed status prediction without modifying target, if not supported the action will be skipped.

diff_mode none

Will return details on what has changed (or possibly needs changing in check_mode), when in diff mode

platform Platform: posix

Target OS/families that can be operated against

raw full

Indicates if an action takes a ‘raw’ or ‘free form’ string as an option and has it’s own special parsing of it

Notes Note

If you want to run a command through the shell (say you are using <, >,

, and so on), you actually want the ansible.builtin.shell module instead. Parsing shell metacharacters can lead to unexpected commands being executed if quoting is not done correctly so it is more secure to use the ansible.builtin.command module when possible.

creates, removes, and chdir can be specified after the command. For instance, if you only want to run a command if a certain file does not exist, use this.

Check mode is supported when passing creates or removes. If running in check mode and either of these are specified, the module will check for the existence of the file and report the correct changed status. If these are not supplied, the task will be skipped.

The executable parameter is removed since version 2.4. If you have a need for this parameter, use the ansible.builtin.shell module instead.

For Windows targets, use the ansible.windows.win_command module instead.

For rebooting systems, use the ansible.builtin.reboot or ansible.windows.win_reboot module.

If the command returns non UTF-8 data, it must be encoded to avoid issues. This may necessitate using ansible.builtin.shell so the output can be piped through base64.

See Also See also

ansible.builtin.raw Executes a low-down and dirty command.

ansible.builtin.script Runs a local script on a remote node after transferring it.

ansible.builtin.shell Execute shell commands on targets.

ansible.windows.win_command Executes a command on a remote Windows node.

Examples

• name: Return motd to registered var ansible.builtin.command: cat /etc/motd register: mymotd

free-form (string) arguments, all arguments on one line

• name: Run command if /path/to/database does not exist (without ‘args’) ansible.builtin.command: /usr/bin/make_database.sh db_user db_name creates=/path/to/database

free-form (string) arguments, some arguments on separate lines with the ‘args’ keyword

‘args’ is a task keyword, passed at the same level as the module

• name: Run command if /path/to/database does not exist (with ‘args’ keyword) ansible.builtin.command: /usr/bin/make_database.sh db_user db_name args: creates: /path/to/database

‘cmd’ is module parameter

• name: Run command if /path/to/database does not exist (with ‘cmd’ parameter) ansible.builtin.command: cmd: /usr/bin/make_database.sh db_user db_name creates: /path/to/database

• name: Change the working directory to somedir/ and run the command as db_owner if /path/to/database does not exist ansible.builtin.command: /usr/bin/make_database.sh db_user db_name become: yes become_user: db_owner args: chdir: somedir/ creates: /path/to/database

argv (list) arguments, each argument on a separate line, ‘args’ keyword not necessary

‘argv’ is a parameter, indented one level from the module

• name: Use ‘argv’ to send a command as a list - leave ‘command’ empty ansible.builtin.command: argv: - /usr/bin/make_database.sh - Username with whitespace - dbname with whitespace creates: /path/to/database

• name: Run command using argv with mixed argument formats ansible.builtin.command: argv: - /path/to/binary - -v - –debug - –longopt - value for longopt - –other-longopt=value for other longopt - positional

• name: Safely use templated variable to run command. Always use the quote filter to avoid injection issues ansible.builtin.command: cat {{ myfile|quote }} register: myoutput Return Values Common return values are documented here, the following are the fields unique to this module:

Key

Description

cmd list / elements=string

The command executed by the task.

Returned: always

Sample: [“echo”, “hello”]

delta string

The command execution delta time.

Returned: always

Sample: “0:00:00.001529”

end string

The command execution end time.

Returned: always

Sample: “2017-09-29 22:03:48.084657”

msg boolean

changed

Returned: always

Sample: true

rc integer

The command return code (0 means success).

Returned: always

Sample: 0

start string

The command execution start time.

Returned: always

Sample: “2017-09-29 22:03:48.083128”

stderr string

The command standard error.

Returned: always

Sample: “ls cannot access foo: No such file or directory”

stderr_lines list / elements=string

The command standard error split in lines.

Returned: always

Sample: [{“u’ls cannot access foo”: “No such file or directory’”}, “u’ls \u2026’”]

stdout string

The command standard output.

Returned: always

Sample: “Clustering node rabbit@slave1 with rabbit@master \u2026”

stdout_lines list / elements=string

The command standard output split in lines.

Returned: always

Sample: [“u’Clustering node rabbit@slave1 with rabbit@master \u2026’”]

Authors Ansible Core Team

Michael DeHaan

Collection links Issue Tracker Repository (Sources) Communication © Copyright Ansible project contributors. Last updated on Dec 22, 2025.